Question: In his chemistry class, Kevin took 4 quizzes. His scores were 90, 92, 81, and 81. What was his average score on the quizzes?
Explanation: The average is the sum of his scores divided by the number of scores. There are 4 scores and their sum is $90 + 92 + 81 + 81 = 344$ His average score is $344 \div 4 = 86$.